EXTREMELY FRUSTRATED! Trying to reinstall pre-alpha lower unit!

[mnmattie]

Pre-Alpha lower unit worked great in forward and reverse no problem. But it needed a new impeller, well I disassembled it from the upper unit, installed new impeller kit, reassembled, had trouble reinstalling as it would have a 1/4 gap all around and stop. tried a few times and finally got it to go (yes i had the throttle in forward and the lower unit in forward) throw it all together, hook up muffs to test and...........NO FORWARD OR REVERSE! Great so I disassembeled it again and the brass/bronze shaft that connects the gear select between the upper and lower unit has alot of slop in it

here it sits by itself hanging low and really sloppy

and here i can push it up with my finger up into the case (bwtween 1/4-3/8 free travel)

another angle (yes i'm no photographer)

and here's a pic of the lower unit.

I'm assuming that this shift shaft is what's giving me problems with hanging up and by the time i wiggle the crap out of the lower unit to finally get it to engage, i misaligh the slots and that's what's causing me to lose my shifting abilities.

is it normal for the shaft between the upper and lower case to have this much slop?

-Mattie

 

[ziggy]

Re: EXTREMELY FRUSTRATED! Trying to reinstall pre-alpha lower unit!

looks like good photography to me man.

is it normal for the shaft between the upper and lower case to have this much slop?

yep, i believe so. mine does anyways. it's a real loose fit till the two half's are mated, then it'll be ok. also, don't forget the washer on top of the lower shift shaft. don't look like it's in place in the pics. w/o that washer, it'll prevent proper shifting also i believe..

the shift shaft in question has given me grief too. best remedy i had was to use two rubber bands and help support it for install. a better remedy yet is to assemble the upper to the lower on the bench. yes, it'll cause to to take the drive off. but there's pm that can be accomplished while its off + ya just won't beleive how much easier it is to mate the upper to the lower when it's on the bench. much, much easier...

 

[mnmattie]

Re: EXTREMELY FRUSTRATED! Trying to reinstall pre-alpha lower unit!

hmmm yeah i can see how mating the lower and upper is alot easier on a bench.


so how hard is it to mate the upper unit into the motor then? tricky to install the driveshaft into the coupler?

-Mattie

 

[HT32BSX115]

Re: EXTREMELY FRUSTRATED! Trying to reinstall pre-alpha lower unit!

Howdy,

Yeah, you're not alone in having some frustration reinstalling an older "lower".

There's a couple things you can do that will help it all go together.

Yes, you do need to be in "FWD" when it goes together. BOTH the actual shift dogs need to be engaged, AND the actual shift "foot' need to be in the right position or it either won't go together or it will be misaligned when you slide the whole mess together.

The shift "foot" (above) needs to be aligned with the "shoe" (the loose shift shaft with the female splines ,can we say that?) so it will slide in when you push the drive back on (if it's removed).


The easiest way to do this it to use a bungee to put a little pressure on the dogs (via the prop) so the shaft doesn't move while you're putting it all together.

When the shift shaft is moved into the FWD position, you can put the bungee on the prop to apply pressure on the prop in the REVERSE direction and that will keep the dogs engaged (don't make it so tight that it actually turns the prop)

Then, when you slide the "lower" up into the "upper", you can move the prop (in the reverse direction) a little to align the vertical drive shaft to get those splines aligned. As you do this ensure that the shift foot is also aligned. (you may have to move it a little. too. )

It's completely normal for the upper shift shaft to be loose in it's hole since it's completely supported by the splined shift shaft below and the foot above.....

If you have the upper on the gimbal, it is usually a little harder since you can't move the upper shift shaft left or right as much as you can when the "foot" is out of the "shoe" (when the drive is off)

Actually you could probably just slide the drive back enough to disengage the foot from the shoe so you can move it a little as you put the lower back on.


If you haven't had the drive off, you need to remove it anyway to check the alignment.

Pull it check your alignment, then put it back together (lower to upper) before you put the drive back on the gimbal. It will be much easier.

You probably need to get a service manual and alignment tool too


Cheers,


Rick

 

[Apollo75]

Re: EXTREMELY FRUSTRATED! Trying to reinstall pre-alpha lower unit!

Well, this year was the first year I have changed my impeller. Got some great help here from many kind people.

All went well when I learned to keep my hands off the shafts --- I finally figured out how the shifting works and used a pair of water pump pliers to ease it into gear while turning the shaft and then did not touch it. I greased up the shafts, main drive and shifting ---- I used some anti-freeze on my fingers to lube the ends of the plastic water tube and inserted it into the lower --- wiggled the lower unit it a few times while lifting into place and it slid right in

Good Luck

OFM

 

[Fishermark]

Re: EXTREMELY FRUSTRATED! Trying to reinstall pre-alpha lower unit!

You have simply forgotten the stainless washer pictured below:

 

[Fishermark]

Re: EXTREMELY FRUSTRATED! Trying to reinstall pre-alpha lower unit!

Also - you ought to remove the o ring from the top of the drive shaft. Mercruiser discovered it causes more problems than in solves. Later models do not even have the groove for the oring.

 

[Apollo75]

Re: EXTREMELY FRUSTRATED! Trying to reinstall pre-alpha lower unit!

Yes, on the pictures you are missing the two washers ---- I don't know what they do for shifting --- I know they will keep junk and exhaust off the seal area there and provide a wear surface for the coupler ( how much could it wear ? )

Since it is a major shift problem I hear --- > the washers must also lift the shift shaft brass coupler up so it fully engages the upper shift shaft mechanism. What else could it be ?


Added: That O-ring I found out while reading is to help keep grease in the coupling area where the lower shaft slides into the upper shaft. Whether it works or not I was told the newer units do not have an O-ring. I did notice my upper has a seal in that area ---- probably for the same reason and to keep water out. I just lubed my lower splines well and keep the O-ring on and put it together.

Good Luck

OFM

 

[jtybt]

Re: EXTREMELY FRUSTRATED! Trying to reinstall pre-alpha lower unit!

Like fishmark said. The washer acts as a spacer and raises the shift lever(foot) high enuff to engage the 'shoe' in the bell housing. If you sick your head under the drive as they go together you can see what I'm talking about.




....is that oil sitting around the lower shift shaft cavity?

 

[ziggy]

Re: EXTREMELY FRUSTRATED! Trying to reinstall pre-alpha lower unit!

I just lubed my lower splines well and keep the O-ring on and put it together

don't it cause ya grief when ya assemble it? don't ya always wonder if it ain't slipped out of it's slot... leave it off. the proof it's not needed is

Later models do not even have the groove for the oring.

that would be a model 1r (revised) or 1mr (major revised).

....is that oil sitting around the lower shift shaft cavity?

good catch, looks like mercruiser high performance gear lub to me too. that area is exposed to water, not gear lub. at least on my 1 drive it is. i'd assume a alpha1 too... this would be a real concern to me unless ya spilled gear lub there some how... it sure looks like clean lub????

 

[Apollo75]

Re: EXTREMELY FRUSTRATED! Trying to reinstall pre-alpha lower unit!

Don't know Ziggy

There is a driven shaft seal way up there --- then there is the cavity where you pack grease on the splines of the lower unit and shove it into the driven gear in the upper --- there is an O-ring to keep the grease from flinging out and a seal to keep water from going in there washing the grease out --- the area will see no lube High Performance or other wise unless the driven seal is leaking.

Is that what you two are referring too ?


OFM

 

[ziggy]

Re: EXTREMELY FRUSTRATED! Trying to reinstall pre-alpha lower unit!

Apollo75, you may find this an interesting read... http://forums.iboats.com/showthread.php?t=231825
don't know where achris has been lately, but man, he knew about boats. he's helped me on many of my problems i had and he gave good info/professional advise, imho, to many folks, including me. anyways. that thread helped me decide. i don't have my oring in place. no ramifications that i'm aware of...

 

[Apollo75]

Re: EXTREMELY FRUSTRATED! Trying to reinstall pre-alpha lower unit!

Thank you Ziggy:

I did consider all the great information you and others gave me before my impeller change. About that time I found the article on what that O-ring does --- I know you and others said it did not need it. I also read about other peoples shafts wearing in that area. I decided it has been that way for 34-years and the shaft looked like new. So, I decided with the lower seal and O-ring to grease it up good and install it like it was.

The lower seal would keep water out --- the grease would keep wear down on the shaft splines and the O-ring couldn't hurt anything even if it came off. Should the driven seal leak the lower seal will be secondary safeguard and may hold until the lower unit comes off again for a new impeller and at that time I will see it immediately from the lube running down the shaft when I remove it.


OFM

 

[mnmattie]

Re: EXTREMELY FRUSTRATED! Trying to reinstall pre-alpha lower unit!

thanks for the replys guys.

I did pick up a Seloc manual and read it a few times and kinda got the jist of it before pulling it apart for the first time.

Probably going to end up pulling the upper unit off of the gimbal and reassemble it on the bench and probably check the u joints at the same time then.

yes I noticed that there was no washer ever in there, i went and picked one up today for reassembly.

as far as the oil, that was my fault. the first time i removed the lower unit the gear lube smellet like burnt oil. so failure to find the fill hole and having a blonde moment (while not even being blonde) i attempted to fill the unit through the upper vent hole. that made for quite a mess. so i assume the gear lube in the shift cavity came from there.

I will try this again and see where it gets me.

I will also check into the alignment tool needed and alignment procedure so i know what to look for when I remove the upper unit

Mattie

 

[ziggy]

Re: EXTREMELY FRUSTRATED! Trying to reinstall pre-alpha lower unit!

I did pick up a Seloc manual and read it a few times and kinda got the jist of it before pulling it apart for the first time.

many of the mercruiser service manuals are available from the adults only sticky at the top of this i/o forum. look at #9. ya got pre alpha. you'll have to decide which one. the oem manual is the only way to go. it has the facts in it.

Probably going to end up pulling the upper unit off of the gimbal and reassemble it on the bench and probably check the u joints at the same time then.

yep, good idea...

yes I noticed that there was no washer ever in there, i went and picked one up today for reassembly.

that'll be a winner for sure..

I will also check into the alignment tool needed and alignment procedure so i know what to look for when I remove the upper unit

yep, get one. i procrastinated and i knew i needed one. might as well get it. you'll be happier knowing ya can check alignment anytime ya feel the urge...

I decided it has been that way for 34-years and the shaft looked like new.

i used to feel that way. but i've been conviced other wise..

and the O-ring couldn't hurt anything even if it came off.

did you read the part by achris where he talks about that oring coming off and wedgeing in between the bottom seal of the drive and the drive shaft, thus defeating both seals? worse part is ya don't know if it occured till after the facts... food for thought..

 

[Apollo75]

Re: EXTREMELY FRUSTRATED! Trying to reinstall pre-alpha lower unit!

Your funny Ziggy

Do you know how dry of lube that O-ring would have to be to get grabbed by the shaft and wedged under that seal ----> one in a Googolplex


Keep Boating

OFM

 

[jtybt]

Re: EXTREMELY FRUSTRATED! Trying to reinstall pre-alpha lower unit!

If that oil sitting in the forward cavity of the lower unit happened while trying to fill the drive, maybe you forgot to install the quad ring in the port rail between the upper and lower halves. It's the transfer tube that connects the gear cases.

 

[edb007]

Re: EXTREMELY FRUSTRATED! Trying to reinstall pre-alpha lower unit!

Just like to thank the person who posted about the missing washer. I had a friend pull the drive off and the washer and gasket must have slipped off. Put about 10 hours into it before hit on this post that explained why the shifter dog was not engaging into the upper. Found the missing parts and it worked.

BIG THANK YOU!

 

[Bondo]

Re: EXTREMELY FRUSTRATED! Trying to reinstall pre-alpha lower unit!

Ayuh,.... Welcome Aboard Ed,... Another lurker comes into the membership...

Normal operating procedure would be to tell you to post your Own thread about Your problems so We could help ya,...
But,....
Posting to the archives with a Great Big, Thank You,...

That's a totally New 1 on Me....

Again,... Welcome Aboard...